pilotclient/src/blackmisc/valueobject_policy.h

/* Copyright (C) 2014
 * swift project Community / Contributors
 *
 * This file is part of swift project. It is subject to the license terms in the LICENSE file found in the top-level
 * directory of this distribution and at http://www.swift-project.org/license.html. No part of swift project,
 * including this file, may be copied, modified, propagated, or distributed except according to the terms
 * contained in the LICENSE file.
 */

//! \file

#ifndef BLACKMISC_VALUEOBJECT_POLICY_H
#define BLACKMISC_VALUEOBJECT_POLICY_H

#include "tuple.h"
#include <QMetaType>
#include <QDBusMetaType>

namespace BlackMisc
{
    template <class>
    struct CValueObjectStdTuplePolicy;

    namespace Policy
    {
        namespace Private
        {
            //! \private Alias for the policy of the base class of T
            template <class T>
            using Inherit = CValueObjectStdTuplePolicy<typename T::base_type>;

            //! \private
            using BlackMisc::Private::EncapsulationBreaker;
        }

        namespace MetaType
        {
            //! CValueObjectStdTuple default registerMetadata policy
            struct Default
            {
                //! Register with QMetaType
                template <class T, class...>
                static void registerImpl() { qRegisterMetaType<T>(); qDBusRegisterMetaType<T>(); }
            };

            //! CValueObjectStdTuple registerMetadata policy which inherits the policy of the base class
            struct Inherit
            {
                //! Register with QMetaType
                template <class T, class Base = T>
                static void registerImpl() { Private::Inherit<Base>::MetaType::template registerImpl<T, typename Base::base_type>(); }
            };

            //! CValueObjectStdTuple registerMetadata policy which also registers QList<T>
            struct DefaultAndQList
            {
                //! Register with QMetaType
                template <class T, class...>
                static void registerImpl() { Default::registerImpl<T>(); Default::registerImpl<QList<T>>(); }
            };
        }

        namespace Equals
        {
            //! CValueObjectStdTuple policy for a class which should not have an equals operator
            struct None
            {
                //! Inner class template which actually bestows the operators via the Barton-Nackman trick
                template <class T, class>
                struct Ops {};
            };

            //! CValueObjectStdTuple equals operator policy which inherits the policy of the base class
            struct Inherit
            {
                //! Inner class template which actually bestows the operators via the Barton-Nackman trick
                template <class T, class Base>
                struct Ops : public CValueObjectStdTuplePolicy<Base>::Equals::template Ops<T, typename Base::base_type> {};
            };

            //! CValueObjectStdTuple policy for a class whose meta tuple members can be compared by the equals operator
            struct MetaTuple
            {
                //! Inner class template which actually bestows the operators via the Barton-Nackman trick
                template <class T, class>
                struct Ops : private Private::EncapsulationBreaker
                {
                    //! Equals operator
                    friend bool operator ==(const T &a, const T &b) { return Private::EncapsulationBreaker::toMetaTuple(a) == Private::EncapsulationBreaker::toMetaTuple(b); }

                    //! Not equals operator
                    friend bool operator !=(const T &a, const T &b) { return !(a == b); }
                };
            };

            //! Some classes define their own custom equals operator; this policy provides a not equals operator which simply negates the result
            struct OwnEquals
            {
                //! Inner class template which actually bestows the operators via the Barton-Nackman trick
                template <class T, class>
                struct Ops
                {
                    //! Not equals operator; class T already has its own equals operator
                    friend bool operator !=(const T &a, const T &b) { return !(a == b); }
                };
            };
        }

        namespace LessThan
        {
            //! CValueObjectStdTuple policy for a class which should not have a less than operator
            struct None
            {
                //! Inner class template which actually bestows the operators via the Barton-Nackman trick
                template <class T, class>
                struct Ops {};
            };

            //! CValueObjectStdTuple less than operator policy which inherits the policy of the base class
            struct Inherit
            {
                //! Inner class template which actually bestows the operators via the Barton-Nackman trick
                template <class T, class Base>
                struct Ops : public CValueObjectStdTuplePolicy<Base>::LessThan::template Ops<T, typename Base::base_type> {};
            };

            //! CValueObjectStdTuple policy for a class whose meta tuple members can be compared by the less than operator
            struct MetaTuple
            {
                //! Inner class template which actually bestows the operators via the Barton-Nackman trick
                template <class T, class>
                struct Ops : private Private::EncapsulationBreaker
                {
                    //! Less than operator
                    friend bool operator <(const T &a, const T &b) { return Private::EncapsulationBreaker::toMetaTuple(a) < Private::EncapsulationBreaker::toMetaTuple(b); }

                    //! Greater than operator
                    friend bool operator >(const T &a, const T &b) { return b < a; }

                    //! Greater or equal operator
                    friend bool operator >=(const T &a, const T &b) { return !(a < b); }

                    //! Less or equal operator
                    friend bool operator <=(const T &a, const T &b) { return !(b < a); }
                };
            };

            //! Some classes define their own custom less than operator; this policy implements other comparison operators in terms of this one
            struct OwnLessThan
            {
                //! Inner class template which actually bestows the operators via the Barton-Nackman trick
                template <class T, class>
                struct Ops
                {
                    //! Greater than operator; class T already has its own less than operator
                    friend bool operator >(const T &a, const T &b) { return b < a; }

                    //! Greater or equal operator; class T already has its own less than operator
                    friend bool operator >=(const T &a, const T &b) { return !(a < b); }

                    //! Less or equal operator; class T already has its own less than operator
                    friend bool operator <=(const T &a, const T &b) { return !(b < a); }
                };
            };
        }

        namespace Compare
        {
            //! CValueObjectStdTuple policy for a class without polymorphic comparison support
            struct None
            {
                //! Policy implementation of CValueObject::compareImpl
                template <class T, class...>
                static bool compareImpl(const T &, const T &) { qFatal("Not implemented"); return 0; }
            };

            //! CValueObjectStdTuple polymorphic comparison policy which inherits the policy of the base class
            struct Inherit
            {
                //! Policy implementation of CValueObject::compareImpl
                template <class T, class Base = T>
                static bool compareImpl(const T &a, const T &b) { return Private::Inherit<Base>::Compare::template compareImpl<T, typename Base::base_type>(a, b); }
            };

            //! CValueObjectStdTuple policy for a class with default metatuple-based polymorphic comparison support
            struct MetaTuple : private Private::EncapsulationBreaker
            {
                //! Policy implementation of CValueObject::compareImpl
                template <class T, class...>
                static bool compareImpl(const T &a, const T &b) { return compare(Private::EncapsulationBreaker::toMetaTuple(a), Private::EncapsulationBreaker::toMetaTuple(b)); }
            };

            //! CValueObjectStdTuple policy for a class which implements its own custom poylymorphic comparison support
            struct Own
            {
                //! Policy implementation of CValueObject::compareImpl
                template <class T, class...>
                static bool compareImpl(const T &, const T &) { return 0; }
            };
        }

        namespace Hash
        {
            //! CValueObjectStdTuple policy for a class without hashing support
            struct None
            {
                //! \copydoc BlackMisc::CValueObject::getHashValue
                template <class T, class...>
                static uint hashImpl(const T &) { qFatal("Not implemented"); return 0; }
            };

            //! CValueObjectStdTuple hashing policy which inherits the policy of the base class
            struct Inherit
            {
                //! \copydoc BlackMisc::CValueObject::getHashValue
                template <class T, class Base = T>
                static uint hashImpl(const T &obj) { return Private::Inherit<Base>::Hash::template hashImpl<T, typename Base::base_type>(obj); }
            };

            //! CValueObjectStdTuple policy for a class with default metatuple-based hashing support
            struct MetaTuple : private Private::EncapsulationBreaker
            {
                //! \copydoc BlackMisc::CValueObject::getHashValue
                template <class T, class...>
                static uint hashImpl(const T &obj) { return qHash(Private::EncapsulationBreaker::toMetaTuple(obj)); }
            };

            //! CValueObjectStdTuple policy for a class which implements its own custom hashing support
            struct Own
            {
                //! \copydoc BlackMisc::CValueObject::getHashValue
                template <class T, class...>
                static uint hashImpl(const T &) { return 0; }
            };
        }

        namespace DBus
        {
            //! CValueObjectStdTuple policy for a class without DBus marshalling support
            struct None
            {
                //! \copydoc BlackMisc::CValueObject::marshallToDbus
                template <class T, class...>
                static void marshallImpl(QDBusArgument &, const T &) { qFatal("Not implemented"); }

                //! \copydoc BlackMisc::CValueObject::unmarshallFromDbus
                template <class T, class...>
                static void unmarshallImpl(const QDBusArgument &, T &) { qFatal("Not implemented"); }
            };

            //! CValueObjectStdTuple marshalling policy which inherits the policy of the base class
            struct Inherit
            {
                //! \copydoc BlackMisc::CValueObject::marshallToDbus
                template <class T, class Base = T>
                static void marshallImpl(QDBusArgument &arg, const T &obj) { Private::Inherit<Base>::DBus::template marshallImpl<T, typename Base::base_type>(arg, obj); }

                //! \copydoc BlackMisc::CValueObject::unmarshallFromDbus
                template <class T, class Base = T>
                static void unmarshallImpl(const QDBusArgument &arg, T &obj) { return Private::Inherit<Base>::DBus::template unmarshallImpl<T, typename Base::base_type>(arg, obj); }
            };

            //! CValueObjectStdTuple policy for a class with default metatuple-based DBus marshalling support
            struct MetaTuple : private Private::EncapsulationBreaker
            {
                //! \copydoc BlackMisc::CValueObject::marshallToDbus
                template <class T, class...>
                static void marshallImpl(QDBusArgument &arg, const T &obj) { arg << Private::EncapsulationBreaker::toMetaTuple(obj); }

                //! \copydoc BlackMisc::CValueObject::unmarshallFromDbus
                template <class T, class...>
                static void unmarshallImpl(const QDBusArgument &arg, T &obj) { arg >> Private::EncapsulationBreaker::toMetaTuple(obj); }
            };

            //! CValueObjectStdTuple policy for a class which implements its own custom DBus marshalling support
            struct Own
            {
                //! \copydoc BlackMisc::CValueObject::marshallToDbus
                template <class T, class...>
                static void marshallImpl(QDBusArgument &, const T &) {}

                //! \copydoc BlackMisc::CValueObject::unmarshallFromDbus
                template <class T, class...>
                static void unmarshallImpl(const QDBusArgument &, T &) {}
            };
        }

        namespace Json
        {
            //! CValueObjectStdTuple policy for a class without JSON support
            struct None
            {
                //! \copydoc BlackMisc::serializeJson
                template <class T, class...>
                static QJsonObject serializeImpl(const T &) { qFatal("Not implemented"); return {}; }

                //! \copydoc BlackMisc::deserializeJson
                template <class T, class...>
                static void deserializeImpl(const QJsonObject &, T &) { qFatal("Not implemented"); }
            };

            //! CValueObjectStdTuple JSON policy which inherits the policy of the base class
            struct Inherit
            {
                //! \copydoc BlackMisc::serializeJson
                template <class T, class Base = T>
                static QJsonObject serializeImpl(const T &obj) { return Private::Inherit<Base>::Json::template serializeImpl<T, typename Base::base_type>(obj); }

                //! \copydoc BlackMisc::deserializeJson
                template <class T, class Base = T>
                static void deserializeImpl(const QJsonObject &json, T &obj) { Private::Inherit<Base>::Json::template deserializeImpl<T, typename Base::base_type>(json, obj); }
            };

            //! CValueObjectStdTuple policy for a class with default metatuple-based JSON support
            struct MetaTuple : private Private::EncapsulationBreaker
            {
                //! \copydoc BlackMisc::serializeJson
                template <class T, class...>
                static QJsonObject serializeImpl(const T &obj) { return BlackMisc::serializeJson(Private::EncapsulationBreaker::toMetaTuple(obj)); }

                //! \copydoc BlackMisc::deserializeJson
                template <class T, class...>
                static void deserializeImpl(const QJsonObject &json, T &obj) { BlackMisc::deserializeJson(json, Private::EncapsulationBreaker::toMetaTuple(obj)); }
            };

            //! CValueObjectStdTuple policy for a class which implements its own custom JSON support
            struct Own
            {
                //! \copydoc BlackMisc::serializeJson
                template <class T, class...>
                static QJsonObject serializeImpl(const T &) { return {}; }

                //! \copydoc BlackMisc::deserializeJson
                template <class T, class...>
                static void deserializeImpl(const QJsonObject &, T &) {}
            };
        }
    }
}

#endif